Equipment for moored airships



Nov. 14, 1933. M Q. KRELL 1,935,271

EQUIPMENT FOR MOORED AIRSHIPS Filed March 7, 1932 4 Sheets-Sheet l 1 Inventor; fig 2 /jwh Nov. 14, 1933. o. KRELL 1,935,271

EQUIPMENT FOR MOORED AIRSHIPS Filed March 7, 1952 4 sheets-sheet 2 Nov. 14, 1933. O KRELL 1,935,271

EQUIPMENT FOR MOORED AIRSHIPS Filed March 7, 1932 4 Sheets-Sheet 3 Nov. 14, 1933. o. KRELL EQUIPMENT FOR MOORED AIRSHIPS Filed March 7, 1932 4 sheets sheet 4 Inventor:

@MIZJA Patented Nov. 14, 1933 arENrore-ice EQUIPMENT-FORMOORED Amsnlrs om; men, Berlin-Dahlem, Germany Application March 7, 1932, Serial No. 597,253,

and in Germany December18, 1928 l 9 Claims.

My inventionrelates to improvements in equip ment for moored airships.

The" auxiliary equipment for airships moored on masts is still far from perfect, whether a high or low mast, a separately mounted or a mast mounted above the inlet opening of a rotary hangar is employed.

It is above all necessary to maintain the airship tied up at or anchored to the mast in a steady horizontal position without preventing it from giving way in the horizontal direction or from swinging around the mast.

To protect an airship moored to a high mast against excessive vertical oscillations, I have suggested the employment of ballast bodies connected in the manner of the links of a chain, more particularly a plurality of chains combined into a tassel in such a way that at thetop a single chain only is connected to the stern of the airship, which by the addition of further chains becomes more and more forked towards the free end so that a chain tassel is formed which becomes gradually heavier towards the end.

The main drawback in the application of such ballast chains, which steady the airship very j satisfactorily as far as purely vertical movements are concerned is that during the horizontal swinging movements of the airship the chain must be dragged along the ground and that in this way a considerable resistance is opposed to the horizontal movements which on the airship tied up at the nose and on the other hand held back bythe dragging chain must necessarily have the action that under the action of a cross wind the axis of the airship describes the convex surface of a cone, so that if the cross wind is sufficiently strong the stern of the ship may come in contact with the ground.

It thus suggests itself and has already been proposed to accommodate the ballast members or "chain one. car or trolley and to let the car together with the chain be dragged along by the swinging airship. This is hardly an improvement however, because although the car will be made as light as possible it will still have a considerable weight in order to enable it to carry the weight of the chain, so that the power required for its acceleration will notbe much less than the resistance of the chain hauled along the ground.

Conditions are somewhat different if the after portion of the ship near the stern is directly secured to a car or truck which'describes a circular path around the point of attachment of the moored ship, as has repeatedly been done when mooring the airship to low masts, so-called stub masts. For this circular path a railroad track is usually laid, as the car moving over rough ground would. seriously jolt the airship, which is comparatively rigid owing .to its great mass. A cushioning device strong enough to absorb these shocks is not easy to design. This arrangement has the further disadvantage that'this car secured to the ship like the car carrying the ballast chain mentioned'abo've must bemade as light as possible so as not to oppose an excessively high'resistance to its acceleration in the event of "a cross wind striking the ship, so that the airship held fast at the bow and thes'tern is subjected to a bending strain. As compared with this the airship rnooredfto high mast'and'f steadied merely by chains has'a certain resiliency and thus an advantage over the befcre'clescribed construction. To this must be added thattliecar secured to 'the' stern of the airship 'shouldbe so heavy that it cannot be lifted up'into the airby vertical gusts of ground wind. The conditions for the construction ofithe car are thus contradictory. I

, To eliminate all these drawbacks, I'employ means to connect the airship resiliently .withthe' car and reduce the'power for acceleratingand car witha self-contained propulsion system and brakes adapted to befjr'endered operative and inoperative by the lateral starting and stopping movements of the airship. This idea 1 underlying my highly improves the utility of the ballast chain of variable 'orftowards the end increasing weight. The damping of the vertical oscillations maybe carried to any desired extent-by correspondingly present" invention retarding the cartoa minimum by providingthe choosing the proportions of the chain without increasing the resistancejto thehorizontalswingi'ng motion of the airship. The chain carrying car and also the car to which the after portion of the ship is' secured can now aite'rfproviding it with'self-contained propulsionnieans and'thus enabling it to accelerate itself as; soon as-it receives an impact from' the swinging airshipfbe made" so heavy that it may be considered as an absolutely reliablemeans for steadying moored airships. g II" further oninthisspecification storage batteries are'suggested as sources of power for the self-contained car propulsion system," their high weight is rather an'advantage than a drawback. They have, furthermore, in this case the particularly valuable property that they are always readyior service and dependable to an extent not attained by any other source of power.

The mode of operating the control'gear of the eiil car in the case of high and the low masts will now be explained in greater detail with reference to the examples illustrated in the drawings affixed to my specification and forming part thereof.

Fig. 1 is an elevational view of the main and intermediate cars from the rear of the airship, the airship being shown in section and resting on the cars.

Figs. 2, 3 and 4 are similar views but of respective modifications of my device.

Figs. 5 and 6 are fragmentary elevational views of further respective modifications of my device. In these views an additional indication of another position of the ballast chain is shown in full lines rather than conventional dot-and-dash showing to better illustrate the features of the ballast chain and mooring cables.

Figs. '7 and 8 are longitudinal sectional views of respective modifications of planet wheels or reversing gear D of the devices of Figs. 5 and 6.

Figs. 9 and 10 are longitudinal views, partly in section, of respective modifications of a ca wheel and braking mechanism therefor.

If the airship is moored to a low or stub moor- ,ing mast and it is desired to support it resiliently against vertical forces upon a car located near the stern and, if desired, also upon a second car located at the after portion of the ship nearer the middle of its length, the control motion between car W and the body of the airship L is effected by an auxiliary 'or intermediate car w, Figs. 1 and 2, located between the supporting car proper and the airship. This auxiliary car or carriage w is only capable of movement in the horizontal direction of the railroad track while it is secured against being'vertica'lly lifted off the main car. The carriage or auxiliary car to is on the other hand firmly secured to the airship L. If now the airship is swung sideways by a cross wind, it commences to move together with the auxiliary car w without, however, carrying along the main car W. This leading motion of the auxiliary car.

in relation to the main car is utilized for controlling the main car. If electrical driving means are provided upon the main car the switching of .the motors M, M may be eifected by the auxiliary car directly operating the switch lever S,]Fig. 1, or by means of relays. If the auxiliary car is provided with large wheels 1', r, to facilitate its motion, the brake and the switch lever 71. maybe operated from one of these wheels, r, Fig. 2, or a drum-type controller may be directly mounted upon a wheel axle of the auxiliary car. The lateral movement of the auxiliary car in relation to the main car is of course limited by suitable means, even if the propelling forces should be so proportioned that the auxiliary car never travels right up to the end abutmentsa. The mode of operation of this auxiliary car is as follows: if the airship swings around its point of attachment under the action of 'a cross wind the auxiliary car is displaced in relation to the main car stationary at the time.

The brakes of the main car, which are applied as long and as soon as the airship stands substantially vertically above the center of the main car, are simultaneously lifted off. After releasing the brakes the auxiliary car proceeding along its path switches in the self-contained propulsion system of the main car to a gradually increasing extent and the car follows the airship with increasing acceleration until it reaches her. If the car overtakes the airship because of the action of the cross wind on the airship has ceased idle motion of the auxiliary carriage w.

or because the car has attained a high speed,

the auxiliary car stops behind and, in the reverse order, disconnects first the propulsion system and then applies the brakes as soon as its center stands vertically above the center of the main car. The control process remains the same for right-hand and left-hand swings of the airship owing to the symmetrical arrangement of the parts of the switchgear. The two cars, the car at the stern and the car at the after portion nearer the middle of the airship may each by itself be controlled by utilizing the relative motion (leading and lagging) of the airship. The control of the second car nearer the middle of the ship may also be made dependent upon the movement of the stern car, it being then necessary to take into account the difference in the swinging radii and of the velocities of the two cars. An automatic and correctdistribution of the propulsion forces and velocities over both cars may be obtained by ,a series connection of the electrical driving means stepped in the ratio of the swinging radii.

If value is attached to smooth starting, the Ward-Leonard connection should be chosen as it is particularly suitable for this purpose. It is then necessary to mount a constantly running Leonard converter upon the car. The Ward- Leonard converter set comprises a D. C. generator adapted to be driven at a constant speed by an electric motor directly coupled with it. The electri motor is preferably fed with current from a storage battery mounted on the car itself. The magnetic field of the electric motor M driving the car is constantly and fully excited, while in the exciter line of the generator there is connected a regulating resistance which permits of the excitationand thus the voltage of the generator being regulated from zero or the lowest voltage generated by the remanent magnetism (about 1.5 to 2 Volts) respectively up to the full operating voltage. The armature of the generator is connected in series with the armature of themotor fordriving the car. speed of the car driving motor is directly proportional to the voltage supplied to the armature. In this way the speed of the driving motor may be regulated in very fine steps, and, more particularly, a very smooth starting of the car insured. The regulating resistance for the excitation of the generator is operated by the Instead of a single driving motor for the car a plurality of such motors may equally well be used, the armatures of which are then connected in parallel with one another and in series with the generator armature, or whose armatures are connected in series with one another and with the armature of the generator. The reversal of the direction of motion of the car is attained by the reversal of the field excitation of the generator, while the field excitations of the driving motors remain unchanged.

As source of power for driving the ballast car wind wheels or propellers may, for instance, be employed as shown at P, P in Figs. 3 and 4;. These windwheels are arranged on the car as high as possible above the ground with their axes located parallel to the axis of the airship, Fig. 3. Preferably two air propellers P and P are employed, one on the right and the other on the left of the airship. The wind sweeping along the hull of the airship will continuously drive the full admission windwheels. The blades of the wind wheels P and P have opposite pitch The ' propulsion system of the car.

andthu's' rotate in opposite directions under the to turn on the horizontal drivi'ng shaft a forthe car W, but are adapted'to be alternately clutched "to the'said shaft by means of a suitable clutch by operating the system oflevers or rods H, H,

Z, Z and l, 'l. 'The' clutch or coupling must be so designedthatthe turning motion of the rods iliand Z11 is converted into an axial :motion along the driving shaft a If, for instance, the lever] 2'1 and 11 are connected with a sliding "sleeve. or bushing on the said shaft, which "by means ofa helical face cam contacts with an abutment, this sleeve will move axially upon the driving shaft and clutch one of the planet 'wheels to the driving shaft, for instance, by 'meansof a friction clutch.) 'In the diagrammatic f drawi'ngFig. 3 the clutches k are arranged between the planet wheelsD and the driving chain ,wheel 1". On the driving shaft are mounted belt or rope pulleys, orfchain wheels E which by means of the driving members R and R drive .the,wheels or the axles of the wheels of the car .WL to the, left; due to a variation in the direction :'of the wi'nd,the levers Z, Z and Z, Z are operated If the airship moored ,to .the mast swings by the parallel levers H'and 'I-I moving together with the airship and that planet wheel ofjthev reversing gear ,D is clutched to the driving shaft, which moves the car also towards the left," through the agency of the driving members or chains R and R. If the airship moves towards the right due to thechange in the directio'npf the windl'. the otherplanet wheel D turning in the opposite direction is clutched to the-wheel driving shaft and the car is thus also moved towards the right. 'In the central position of the airship'both clutches or couplings are thrown out of gear so that both planet wheels are able to rotate freely on the driving shaft and the car is no longer driven by the wind wheels.

The employment of windwheels has a further special advantage. Their power depends upon the strength of the wind so'that the propulsion of the car takes place in correspondence with the strengthofthe wind. a

Another example for. the application of a windwheel or propeller drive of the cars supporting the airship would be an arrangement in which the axes of the windwheels stand vertically to the axis ofthe airship, Fig. 4, so that the wind streaming along the hull of the airship flows along the plane of the windwheel and thus does not operate the windwheels. Only if a component develops transversely to the axis of the airship admission of the wind takes place to the control windwheels, which in this case are permanently coupled with the self-contained The provision of special brakes is likewise superfluous because the windwheels themselves take over the task of braking when standing still and reversing.

In contrast with the windwheels with full admission which must be located as high as possible above the ground, as described in the preceding example and illustrated in Fig'. 3, the

windwheels located with their axes transversely to the axis of the airship must be placed at a lower height in order that they may present as large: as possiblea surface to the current of cross wind streaming along underneath the hull of the airship and more particularly-the stern ofjthe airship. This arrangement is similar to the device employed in windmills and which is employed for" automatically setting the plane of the wings'at right angles to the direction of the wind. As the wind wheels P and P are struck from the 'sarne side by'a cross-wind and both are mounted onthe same shaft Q they must have both either right-han'dor left-hand pitch. The rotation of this shaft Q is'transmitted-to the car 'W by two pairs of bevel wheels'F and F mounted on vertical shafts G and'G" which at their lower ends carryworms -J and J which mesh with worm wheels U U mounted on the wheel axles. 'lhe direction of rotation of the wormwheels U and U must be so chosen that the car is able to yield in the direction of cross- 1 winds.

If the airship ,is moored to a high mast, the

deflection, Figs. and 6, which the upper end 0 of the chain tassel Q or, as shown in the drawings, the chain with the upwards gradually decreasing links produces in relation to the chain conveying car W1 when the airship advances ahead of the car, is utilized for making the nec essary control connections. 7 is shown in the braked condition.. These brakes .Bare by means of cables and across a differential gearing D connected to the upper end 0 of the chain tassel and thereby to the airshipherself.

The stationary car whichis adapted to be effected by the movement of the shaft C of these planet wheels. The main or sun'wheels of the differential gearing s, s are designed as cable or rope drums 'orbarrels upon which two ropes Ic,-k'bifurcatingi from the top point of the chain tassel are wound up in opposite direction. The drums are turned in opposite directions by the springs F and I?" so as to hold the two wound-up ropes taut. In this way it happens, as described above, that in the event of a purely vertical movement of the point 0, O,

at which the rope bifurcates, the shaft 0 of the pair of planet wheels does not change its posi-f tionin space. If, however, the bifurcating point is laterally displaced towards O or 0" by a swinging motion of the airship the shaft of the pair of planetwheels is carried along in the same direction by means of the ropes T, T. The deflec-' tion may then be utilized for operating the brakes, for instance the screw operated band-brake shown in Fig. 5 or the switchgear shown in Fig. 6. The greater the lead of the airship in relation to the car, the more propelling means are switched in and the car follows the airship with increasing speed. If the swinging motion of the airship slows down and the car W1 overtakes the ship, the switching motion and thus the switching process are reversed, the propelling means are gradually switched out more and more and finally the brakes are applied when the airship stands tained propulsion system and brake means.

2. In auxiliary equipment for airships moored to masts, a main car located underneath the after portion of the airship, a self-contained propulsion system, including braking means and switchgear mounted upon said car, an intermediate car secured to the airship and adapted to travel along said main car and to permit the swinging airship tolead or lag behind in relation to the main car, and means for utilizing this relative movement of the auxiliary car to the main car for operating said system on the main car.

3. In auxiliary equipment for airships moored to masts, a main car located underneath the after portion of the airship, a self-contained propulsion and braking system, and switchgear mounted upon said car, an intermediate car to which the after portion of the airship is secured and adapted to travel along said main car and to permit the swinging airship to lead or lag behind in relation to the main car and means for utilizing therotary motion of the wheels of said intermediate car for controlling the system to effect starting or braking.

4. In auxiliary equipment for airships moored to masts, cars, to whichthe after portion of the airship is; secured, windwheels fully exposed to the wind and permanently driven, mounted on said cars, and reversing gearing for coupling said windwheels with said cars and adapted to set them in motion in the direction in which the airship leadsor lags behind the cars.

5. In auxiliary equipment for airships moored to masts, cars, to which the after portion of the ship is secured, windwheels mounted on said cars so'arranged that they drive the car then only if the airship is struck by cross winds.

6. In an auxiliary equipment for airships moored to masts, cars to which the after portion of the airship is secured, brakes and electric propulsion. means mounted on said cars, a storage battery for feeding said propulsion means, and a Ward-Leonard converter connected between said battery and said propulsion means.

7. In an auxiliary equipment for airships moored to masts, cars to which the after portion of the airship is connected by means of ballast chains, brakes for said cars, self-contained propulsion means mounted on said cars, and control means for said propulsion means adapted to be operated by the deflection of said ballast chains when the airship leads or lags behind in relation to said car. i

8. In auxiliary equipment for airships moored to masts, cars to which the after portion of the airship is connected by means of draw members, a self-contained propulsion and braking system on said cars and adapted to be controlled by said draw members following the vertical oscillations of the airship.

9. In auxiliary equipment for airships moored to masts, cars to which the after portion of the airship is connected by means of draw members, self-contained propulsion systems and braking means on saidcars and control gear therefor, said system adapted to be controlled by said draw members following the vertical oscillations of the airship, means for keeping said draw members in a taut state, consisting of two cable drums upon which the bifurcated ends of the draw member are wound in opposite directions, springs between said drum tending to turn said drums in opposite directions and intermediate wheels connecting said drums, the shaft of said wheels adapted to maintain its position in space when said draw member is moved up or down but to change it when the draw member is pulledsideways, the change in the position of said shaft being utilized for operating the control gear for the self-contained propulsion and braking system of said car.

" V Om KRELL. 

